DAQ Dictionary – A

In this new series, we’re going to go through the alphabet of data acquisition and try to closely explain the terms used in the field. The articles with new terms will be published twice a week, so make sure you don’t miss any of them if you want to learn the “language” of data acquisition. First things first, we start with A.

Absolute Accuracy

How close the measured value is to the real value.

Acquisition Time

Also known as Sample and Hold Acquisition Time, this term is for the time taken for the sampling circuit to settle to the input voltage.

A/D, A-D, ADC, Analogue-to-Digital Converter

Changes an analog signal into a digital signal appropriate for input to a computer.

Alternating Current (AC)

Electric current whose flow alternates the direction. The number of times the direction changes in one second is called the frequency. The usual waveform of AC is sinusoidal.

Alias

A representation of a high-frequency waveform that has been sampled at a very low rate. Take a look at  anti-alias filter for further understanding.

Ampere (A)

SI unit of electric current.

Amplifier

A circuit that creates a greater output power, voltage or current than was applied at the input.

Amplitude

The size of a signal.

Analogue-to-Digital (A-D) Converter

Changes an analog signal to a digital signal suitable for input to a computer.

Analogue Input

A substantially flexible signal going into a data acquisition device. This is usually a voltage signal. In this case, the data acquisition device will convert the current to a voltage before accepting it.

Analogue Output

A control signal produced by the data acquisition and control equipment.

Anti-Alias Filter

An anti-alias filter that allows passing through the lower occurrence components of a signal but not higher frequencies signals from introducing distortion. Anti-alias filters are indicated agreeing to the sampling rate of the system and there must be one filter per input signal.

Argument

Input parameter to a program.

ASCII

American Standard Code for Information Interchange.
We’re done with the terms from daq starting with A, the following article will be on B-C. Stay tuned and follow the whole series!